An image reading device includes a contact glass, a first lamp, an image sensor, a first lamp, a light absorbing member, and a second lamp. When reading a document, in a first period, the first lamp is turned on while the second lamp is turned off. In a second period, the second lamp is turned on while the first lamp is turned off. On the basis of first image data obtained by reading in the first period and second image data obtained by reading in the second period, the control unit determines whether each pixel in the first image data is a pixel having read document data or not.

An image reading device has a reading module including a light source, an optical system having a mirror array where reflection mirrors are coupled together in the main scanning direction and an aperture stop portion, a sensor where imaging regions for converting the image light imaged by the optical system into an electrical signal are arranged, and a housing, and has a reference drawing pattern determining connection positions between the imaging regions. The reference drawing pattern is composed of a plurality of pixel cut lines arranged to correspond to boundary lines between the reflection mirrors. The optical system is fixed on the housing at one point in the main scanning direction, and the pixel cut lines are arranged such that their distances from the boundary lines in the main scanning direction increase the farther away from the fixed position of the optical system in the main scanning direction.

Provided is an image forming apparatus capable of accurately returning a carriage to a home position without having to turn ON a light source in the process of returning the carriage to the home position. A first reading-position-detection plate is arranged inside of a reading width of a line sensor and outside of a document-image-reading width. A second color region has a length that gradually increases in the main scanning direction as going away from the home position of the carriage. A reading-position-detecting unit detects the length in the main scanning direction of the second color region on the basis of output from the line sensor. A movement-distance-converting unit converts this length to a movement distance to the home position. A movement-control unit causes the carriage to move toward the home position just the movement distance.

In accordance with an embodiment, a lens mirror array includes a plurality of optical elements integrally connected in a first direction. Each optical element includes an incident side lens surface through which light enters the optical element, a ridge located at an edge of the incident side lens surface, a reflection surface on which light incident on the incident side lens surface is reflected, an exit side lens surface through which light reflected by the reflection surface exits the optical element, and a groove surrounding the reflection surface except for a portion adjacent to the ridge, the portion adjacent to the ridge connecting to an adjacent optical element in the plurality of optical elements.

According to the present disclosure, a reading module includes a light source, an optical system, and a sensor. The optical system images, as image light, reflection light of light with which the light source has irradiated a document. The sensor converts the thus imaged image light into an electric signal. The optical system includes a mirror array in which a plurality of reflection mirrors are connected together, and a plurality of aperture stop portions. The reflection mirrors each reflect light at an angle that is different, as seen in a main scanning direction, from an angle at which an adjacent one of the reflection mirrors reflects light. The plurality of aperture stop portions are disposed on one side of the mirror array with respect to an orthogonal direction which is orthogonal to the main scanning direction.

A reading module of the present disclosure is provided with a light source, an optical system, and a sensor. The optical system images, as reading light, reflected light of light radiated from the light source to an illumination object. The sensor converts the reading light imaged by the optical system into an electric signal. The optical system is provided with a mirror array in which a plurality of reflection mirrors are disposed in an array in a prescribed direction and a plurality of aperture stop portions that adjust an amount of the reading light. Each of the reflection mirrors is disposed at a prescribed distance from an adjacent one of the reflection mirrors in a prescribed direction.

Separately providing a shift register for performing serial-to-parallel conversion on a BD signal and a shift register for performing parallel-to-serial conversion on a bit pattern to generate a PWM signal increases the scale of a circuit for adjusting a writing start position in the scanning direction of a light beam. Therefore, the shift register for performing serial-to-parallel conversion on a BD signal and the shift register for performing parallel-to-serial conversion on a bit pattern to generate a PWM signal are configured as a common register.

A reading module includes: a light source for applying light to a document; an optical system for forming an image as image light from reflected light of the light applied from the light source to the document; and a sensor in which a plurality of sensor chips for converting the image light formed by the optical system to electric signals are disposed in adjacency to one another in a main scanning direction. The optical system includes: a mirror array in which a plurality of reflecting mirrors whose reflecting surfaces are aspheric surfaces are coupled in array in the main scanning direction; and apertures provided between the reflecting mirrors and the sensor chips, respectively, to regulate light quantity of the image light reflected by the individual reflecting mirrors. The specular-surface number of the reflecting mirrors is set to an integral multiple of the number of the sensor chips.

A reading apparatus includes an image sensor provided at a terminal end of an optical path, a diaphragm that restricts a quantity of light traveling along the optical path, a concave mirror provided adjacent to and on an upstream side of the diaphragm in the optical path and forms a portion of the optical path, and a convex mirror provided on the upstream side of the concave mirror in the optical path and forms another portion of the optical path.

An image reading chip includes: a first pixel that includes a first photodetector that receives light of a reduced image of a portion of an image and performs photoelectric conversion, and generates a first pixel signal by amplifying a signal generated by the photoelectric conversion; a second pixel that includes a second photodetector that receives light of a reduced image of a portion of the image and performs photoelectric conversion, and generates a second pixel signal by amplifying a signal generated by the photoelectric conversion; and a pseudo pixel that is not involved in reading the image. The first pixel, the second pixel, and the pseudo pixel are arranged along a first side, and the distance between the pseudo pixel and the second side is shorter than the distance between the first pixel and the second side and the distance between the second pixel and the second side.